One would think that coffee might be a culprit in raising blood sugar because of its often negative effect on stress levels. Plus, when you are starting your lower-carb life, it can seem like you have to give up just about everything you love! But scientists believe that the coffee bean itself and the antioxidants it contains help to lower inflammation (see more on inflammation below), which in turn reduces the risk for developing type 2.
A 2014 study by Diabetologia that draws on meta analysis showed that the more coffee people drank, the lower their risk of getting type 2—at the rate of an 11% reduction of risk for every two additional cups consumed! And if you want to ditch the stress potential of coffee, you can drink decaf and still reap some of those benefits, though research suggests that they are much less significant with decaf. On the other hand, however, if you already have type 2, research shows it’s wise to avoid caffeine. Those with type 2 are negatively affected when caffeinated coffee increases stress hormones, like adrenaline—which can get in the way of making insulin and processing sugar—while also reducing proteins that help process sugar, raising glucose levels (and cancelling out any antioxidant benefits).
Why is limiting inflammation—e.g. by either drinking coffee if you’re prediabetic, or avoiding it if you have type 2 diabetes—so important? To be more specific, if you have a high level of sugar in your blood for sustained amount of time, “glucose irritation” in the blood triggers the inflammation of blood vessels. As Diabetes Management explains, this, in turn, generates an immune system response involving the build up of plaque (meant to heal the irritation) that can eventually rupture and damage organs. Of course inflammation does not just come from high blood sugar. It’s also linked to environmental factors, allergies, chemicals, stress, food (including white flours and sugars—hello!), infections, over or under exercising, abdominal fat and high blood pressure.
So, if you are prediabetic, should you make changes to your coffee habit? In my case, I only became aware of the link between coffee and blood sugar recently— which is beyond odd, given that I am a coffee fanatic! Still, I doubt my habits are going to change. I’ve been cutting back on caffeinated coffee over the last few years anyway because of its effects on stress, but thanks to the advent of reasonably tasty decaf espresso, I still drink a fair amount. If anything, I am encouraged to drink more decaf espresso, and hope that I reap the sugar-lowering benefits. I can say definitively that over the course of the 3+ years it took me to get my blood sugar to normal, I was drinking far less caffeinated coffee than in the past, so if I missed some of the antioxidants, I must have made up for it by adjusting other variables (diet, stress and exercise). You too may not think it’s worth drinking more caffeinated coffee because of the stress, and if you still crave the ritual and taste of coffee, you could try the decaf route and hope for the best, as I have. Don’t let the taste of the most decafs discourage you! If you love the strong, brewed stuff, try Peet’s Decaf Dark Roasts—in Major Dickason’s or House Blend (which can be shipped internationally).